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Disorder-induced microscopic magnetic memory

Using coherent x-ray speckle metrology, we have measured the influence of disorder on major loop return point memory (RPM) and complementary point memory (CPM) for a series of perpendicular anisotropy Co/Pt multilayer films. In the low disorder limit, the domain structures show no memory with field cycling-no RPM and no CPM. With increasing disorder, we observe the onset and the saturation of both

Estimation of the biomass and seasonal growth of external mycelium of ectomycorrhizal fungi in the field

In-growth mesh bags were used to quantify the production of external mycelium of ectomycorrhizal (EM) fungi in the field. Colonization of the mesh bags was followed by visual estimation of the amount of mycelium, and by measuring fungal biomarkers (the phospholipid fatty acid (PLFA) 18 : 2 omega6,9 and ergosterol). Mesh bags were placed inside and outside plots that were root isolated in order to

Restricted clinical efficacy of cyclosporin A on rat transient middle cerebral artery occlusion

The immunosuppressant cyclosporin A (CsA) has been shown to have neuroprotective action. The inhibition of both calcineurin activation and mitochondrial permeability transition pore (mtPTP) opening are considered the primary neuroprotective mechanisms of CsA. Here we have evaluated the effect of CsA on significantly reducing infarct size induced by transient middle cerebral artery occlusion (MCAO)

Genetics of sprouting: effects of long-term persistence in fire-prone ecosystems

Fire functional traits (postfire resprouting and seeding) are considered to be adaptations for persisting in fire-prone environments. Although ecological and evolutionary consequences of sprouting have been extensively discussed, within-species genetic variability and structure are unknown. Here we report levels and distribution patterns of genetic polymorphisms in postfire stands of the predomina

Insect monitoring with fluorescence lidar techniques: feasibility study.

We investigate the possibilities of light detection and ranging (lidar) techniques to study migration of the damselfly species Calopteryx splendens and C. virgo. Laboratory and testing-range measurements at a distance of 60 m were performed using dried, mounted damselfly specimens. Laboratory measurements, including color photography in polarized light and spectroscopy of reflectance and induced f

Study of a filtered flamelet formulation for large eddy simulation of premixed turbulent flames

Despite significant advances in the understanding and modelling of turbulent combustion, no general model has been proposed for simulating flames in industrial combustion devices. Recently, the increase in computational possibilities has raised the hope of directly solving the large turbulent scales using large eddy simulation (LES) and capturing the important time-dependant phenomena. However, th

Mast cells and biogenic amines in radiation-induced pulmonary fibrosis

Sprague-Dawley rats were exposed to a single X-ray dose of 30 Gy over the lungs and examined at 1-wk intervals during the following 3 to 8 wk. Mast cells were counted after specific staining with toluidine blue at a low pH and the mast-cell amines, histamine (Hi) and serotonin (5-HT), were measured using high-performance liquid chromatography. Irradiation induced pneumonitis followed by pulmonary

Value added: increasing the power to assess treatment outcome in joint haemorrhages

Subject reports of efficacy of treatment of haemophilia-related joint bleeding are by definition subjective, yet are often the primary outcome in studies comparing therapies. Verbal descriptors such as effective, partially effective, poorly effective, not effective are treated as dichotomous or categorical variables in analyses, lowering the statistical power relative to that which might be achiev

The peritoneal microcirculation in peritoneal dialysis

This paper deals with the peritoneal microcirculation and with peritoneal exchange occurring in peritoneal dialysis (PD). The capillary wall is a major barrier to solute and water exchange across the peritoneal membrane. There is a bimodal size-selectivity of solute transport between blood and the peritoneal cavity, through pores of radius approximately 40-50 A as well as through a very low number

White matter mapping in Alzheimer's disease: A neuropathological study.

White matter disease (WMD) with pervasive non-focal subtotal tissue loss is frequently seen in Alzheimer's disease (AD) upon neuropatholooical examination. Although WMD has varying effects on AD symptoms, accurate clinical detection is difficult due partly to scarcity of correlative structural imaging and histopathological studies. Neuropathological Studies of WMD severity and distribution have be

Simple group graded rings and maximal commutativity

In this paper we provide necessary and sufficient conditions for strongly group graded rings to be simple. For a strongly group graded ring R = circle plus(g is an element of G)R(g) the grading group G acts, in a natural way, as automorphisms of the comrnutant of the neutral component subring R(e) in R and of the center of R(e). We show that if R. is a strongly G-graded ring where R(e), is maximal

Strategies for formaldehyde engines using a single-mode detection in flames and Nd : YAG/OPO laser system

This paper presents technical developments for the detection of formaldehyde (CH2O) using laser-induced fluorescence. The easily accessible third harmonic of the Nd:YAG laser at 355 nm was used for excitation of formaldehyde. In order to investigate potential background fluorescence, e.g., from large molecules such as polyaromatic hydrocarbons, special attention was paid to investigating the possi

Blue stragglers as stellar collision products: the angular momentum question

We investigate the structure and evolution of blue straggler stars, which were formed from direct stellar collisions between main-sequence stars in globular clusters. In particular, we look at the rotational evolution of the products of off-axis collisions. As found in previous work, such blue stragglers initially have too high an angular momentum to contract down to the main sequence. We consider

Sexual selection: an evolutionary force in plants

Sexual selection has traditionally been used to explain exaggerated sexual traits in male animals. Today the concept has been developed and various other sexually related traits have been suggested to evolve in the same manner. In nearly all new areas where the theory of sexual selection has been applied, there has been an intense debate as to whether the application is justified. Is it the case t

Complete high-density lipoproteins in nanoparticle corona.

In a biological environment, nanoparticles immediately become covered by an evolving corona of biomolecules, which gives a biological identity to the nanoparticle and determines its biological impact and fate. Previous efforts at describing the corona have concerned only its protein content. Here, for the first time, we show, using size exclusion chromatography, NMR, and pull-down experiments, tha

Polymeric ultrafiltration membranes and surfactants.

Surfactants have been extensively used in ultrafiltration processes such as membrane cleaning,removal of surfactants or other organic toxic compounds and metal ions from solutions and estimation of interactions at surfactant and membrane interface. The aim of this review is to present the possibilities that arise from the data reported in the literature on the field of ultrafiltration (UF) membran